简介:TheepoxidationofallylchloridewithH2O2onTi-ZSM-5preparedbyisomorphoussubstitutionofHZSM-5withTiCl4gaswasstudied.TheresultsshowthatTi-ZSM-5hasahighcatalyticefficiencyfortheepoxidationofallylchloride.TheH2O2utilizationreaches99.50%whentheallylchloride/H2O2molarratiois>1.Theeffectofsolventspecies,catalystconcentration,H2O2andallylchlorideconcentrationandreactiontemperatureontheepoxidationwasinvestigatedsimultaneously.Itisfoundthatmethanolisthebestsolventforthereaction.Thereactionrateequationwithv=k[Cat.][H2O2]1/2-[C3H5Cl]andtheapparentactivationenergywithEa=63.462kJ/molareobtainedaccordingtothekineticsstudy.
简介:TheternaryCu(Ⅱ)complexwith2,2′-bipyridyl(bipy)andL-methioninte(L-Met)hasbeensynthesizedandcharacterizedbyelementalanalysis,molarconductivity,UV-Visspectra,IRspectraandpH-potentiometrictitrationmethods.Thestructureofthecomplex[Cu(L-Met)(bipy)(H2O)]ClO4·3/8H2OwascharacterizedbytheX-raydiffractionanalysis.Itcrystallizesinthetriclinicsystem,spacegroupP1withfourmoleculesinaunitcellofdimensions,a=0.7656(2)nm,b=1.3142(3)nm,c=2.0596(4)nm,α=97.70(3)°,β=97.96(3)°,γ=94.33(3)°,V=2.0244(8)nm^3,R1=0.0441andwR2=0.0678,Thecrystalcontainsfourcrystallographicallyindependent[Cu(L-Met)(bipy)(H2O)]^+complexes(Cu1-Cu4),havingadistortedsquare-pyramidalgeometrywiththesamecoordinatedatomsaroundeachcoppercenter.Thebaseplaneisoccupiedbytwonitrogenatomsofonebipy,theaminonitrogenatomandonecarboxylateoxygenatomfromeachindependentL-Metmoiety,andonewateroxygenatanaxialposition.CulandCu3areessentiallyenantiomersofCu2andCu4.Thefourmoleculesarepackedwitheachotherbyintermolecularhydrogen-bondingandaromatic-ringstackinginteractions.
简介:Variousenolsof2-acylmethyl-4,4-dimethyl-2-oxazolineswerepreparedinmoderateyieldsviaultrasonicallycatalyzedreactionsof2,4,4-trimethyl-2-oxazolinewitharenecarboxylicestersinthepresenceofUDP-t-BuCl-i-Pr2NHsystem.
简介:Thepaperdealswiththeinfluenceofanodematerialontheefficiencyofdegradationfororganicpollutantsinwatersystem.Theelectrochemicalperformanceoffluorineiondopedleaddioxide(F--PbO2)electrodeforthedegradationofanilinewascomparedwiththatofundopedleaddioxide(PbO2)electrodebyultraviolet-visible(UV-Vis)spectroscopy,linearvoltammetryandotheranalyticalmethods,suchasthemeasurementbychemicaloxygendemandanalyzer,highperformanceliquidchromatographyandscanningelectronmicrography.ItwasshownthatbothPbO2electrodeandF--PbO2electrodecouldmakeanilinebemineralizedcompletelyandhavethesamedegradationcourse,butF--PbO2electrodehasmuchhigherelectrocatalyticactivitythanundopedPbO2electrodefortheelectrochemicaldegradationofaniline.TheexperimentalresultsconfirmthatF--PbO2electrodehasmuchhigherpotentialforoxygenevolutionthanundopedPbO2electrode.
简介:Tris)(η5-cyclopentadienyl-μ-carbonyl-iron)-μ3-nitrosylclusterwasobtainedfromthereactionofcyclopentadienyldicarbonylirondimerwithnitrogenmonoxideinxylene.Theclusterwascharacterizedbyelementalanalyses,IR,MSand1HNMR.Thecrystalstructureof[(η5-C5H5)(μ-CO)Fe]3(μ3-NO).C4H8OwasdeterminedbyX-raydiffractionanalysis.ItcrystallizesintheorthorhombicspacegroupPnma,a=9.053(2),6=10.545(2),c=22.525(4)A,V=2150.3(7)A3,Z=4,Dc=1.68g.cm-3;structuresolutionandrefinementbasedon1141reflectionswithI>3.0(I)(MoKa,A=0.71073A)convergedatR=0.0540.Theinfraredabsorptionbandat1325cm-1oftheμ3-NOinthecluster,whichisredshifted,showsthatμ3-NOisactivated.
简介:Anovelsupportedliquidphasefilmcatalyst:SupportedPdCl2-(n-C4H9)4N+Cl-moltensaltswasfoundtobeaneffectivecatalystwithgoodstabilityforselectivehydrodechlorinationofCCl2F2(CFC-12)toitsalternativesCH2F2andCHClF2.AdditionofCoCl2,GaCl3andCuCl2toPdCl2-(n-C4H9)4N+Cl-modifiesthecatalyticperformanceofsupportedmoltensalts.
简介:传统的化学分析方法分析硅酸盐类矿物样品组份,操作过程繁琐、分析周期长、劳动强度较大,分析结果受分析人员及各种试剂因素影响较大。采用国产能量色散X-射线荧光分析仪,以Li2B4O7和LiBO2作混合熔剂,NH4NO3为氧化剂,熔融制作玻璃熔片,对硅酸盐中SiO2等10个主要成分含量进行同时分析,建立了能量色散X-射线荧光光谱法测定硅酸盐主成分含量的方法,准确度和精密度均达到了规范要求,得到了较为满意的分析结果。
简介:针对多种类不锈钢多元素成分解析问题,应用X射线荧光光谱分析软件UniQuant,采用扩展基本参数法对多元不锈钢、双相不锈钢进行光谱干扰校正和基体校正,重新设定和优化多元不锈钢基体元素的测试条件,计算背景因子、杂质因子、谱线灵敏度系数和光谱重叠系数,测定Si、Mn、S、P、Ni、Cr、Cu、Mo、V、Al、Ti、Nb、Co、Ta、Fe的相对标准偏差在0.04%-3.8%,Ca、Zr、W、As、Sb、Sn的相对标准偏差在5.4%-20.3%,未知样品检测值与认定值比对结果相当理想,Ni、Cr的平均偏差小于0.05%,可以用很少标准样品实现各类型不锈钢多元素成分准确检测,检测范围宽,适用性好。
简介:提出了以自制的标准样品,采用单点法绘制校准曲线,利用X射线荧光光谱仪测定FeSiB非晶薄带样品中硅、硼和铁的含量。对于4个FeSiB非晶合金薄带样品中硅、硼和铁进行了10次测定,其分析结果的相对标准偏差分别为0.4%~0.5%、1.3%~4.2%和0.2%~0.4%。方法的分析结果与火花源原子发射光谱法、化学重量法和电感耦合等离子体原子发射光谱(ICP-AES)法的测定值吻合较好。方法快速、简便,薄带样品无需制样,适用于FeSiB非晶合金薄带的快速成分分析。
简介:合成了N,N′-亚水杨基皮考林酰肼(HL)及其铁配合物[FeL2](C26H20FeN6O4,Mr=536.33).X射线衍射实验结果表明,标题配合物晶体属于正交晶系,空间群为Pbcn,晶体学参数:a=1.4970(1)nm,b=1.51556(9)nm,c=2.0920(2)nm,V=4.7462(6)nm3,Z=8,Dc=1.501Mg·m-3,F(000)=2208,μ(MoKα)=0.682mm-1,R=0.0695,Rw=0.1502.在配合物[FeL2]中,铁(Ⅱ)原子具有扭曲的八面体配位构型,晶体通过分子间氢键作用形成缔合分子对.红外光谱表明,配体在形成配合物后,ν(CO)和ν(CN)红移.电子光谱表明存在π-π*和d-π*的跃迁;荧光光谱表明,配合物金属对配体n-π*激发引起的荧光发射峰有较大的影响.
简介:TheelectrochemicalbehaviorsandthedetectionofNO2-haveattractedincreasingattentionrecentlybecauseoftheimportantrolesplayedbyNO2-inenvironmentandlifeprocesses.Thus,advancedtechniquesforthedetermination,especiallyon-sitedetermination,ofthenitriteinfoods...
简介:TwonewcoenzymeB12analogues,2’,5’-dideoxycytidylcobalamin(2a)and2’,5’-dide-oxyuridinylcobalamin(2b),andtwoothers,2’,5’-dideoxyadenosylcobalamin(2c),and5’-deoxy-thymidylcobalamin(2d)werepreparedbyanimprovedmethod.AllthefouranalogueswereinvestigatedbyUV-visand2D1HNMRspectroscopy.Thecomparisonsanddiscussionabouttheirspectroscopicpropertiesweredone.
简介:Thegeometricalstructuresof2-(2-hydroxyphenyl)pyridine(PP)anditsprotonationstateswereoptimizedbymeansoftheB3LYP/6-31G(d)method.Foralltheselectedsystems,theexistenceofH-bondisinfavorofthestabilityofthesystems.Onthebasisoftheoptimizedgeometricalstructures,theirelectronicspectrumpropertieswerestudiedbytime-dependentdensityfunctionaltheory(TD-DFT)methosdviaahybridfunctionofB3LYPand6-31G(d)basisset.TheTD-DFTcalculationresultpredictstheabsorptionspectrumofPPat324nm(3.82eV),whichisinverygoodagreementwiththeexperimentalvalueof322nm(3.85eV)determinedinsolventchloroform.TheabsorptionspectraofthetwoprotonationstatesbothexertaredshiftinvariouspHmedia.
简介:Twonovelcyclotriphosphazenederivativescontaining6-(4-hydroxyphenyl)-2,2'-bipyridine(hopbp)sidegroups,N_3P_3(dobp)_2(hopbp)_2(1)andN_3P_3(dobp)(hopbp)_4(2)(dobp=2,2'-dioxybiphenyl),weresynthesizedandcharacterized.Thesecompoundsdisplaystrongfluorescentemissionbothinsolutionandinsolidstate.Theirabsorptionandemissionspectraaresensitivetoproton:theadditionofHBF4tothemethanolanddichloromethanesolution(9∶1,volumeratio)ofcompound1ledtoared-shiftfrom350to460nmfortheemissionspectrum,andtheprocesswasalsocharacterizedbyisosbesticpointsofabsorptionspectraat267,287and313nm.